304L vs 316L Stainless Hlau: Qhov Tsawg-Kev Txiav Txim Siab Ntawm Kev Txiav Txim Siab

 

Dab tsi yog qhov sib xyaw ua ke thiab qhov tseem ceeb tshaj plaws ntawm kev ua haujlwm sib txawv?
Ob leeg yog tsawg-carbon (<0.03% C) austenitic steels. 304L is the classic 18-8 stainless (18% Cr, 8% Ni). 316L has a similar base but adds 2-3% Molybdenum. This molybdenum is the single most important difference. It dramatically increases the alloy's resistance to pitting and crevice corrosion, especially in the presence of chloride ions. This makes 316L the minimum recommended grade for most marine, coastal, chemical processing, and pharmaceutical applications, whereas 304L is perfectly suitable for a vast range of less aggressive environments.

Nyob rau hauv txhua txhua hnub thiab kev lag luam ib puag ncig yog qhia 316L tshaj 304L tsis yog-kev sib tham?
Kev qhia txog 316L tsis yog - sib tham tau rau:Marine & Coastal:Nkoj fittings, boardwalks, thiab architecture raug tshuaj tsuag ntsev.Kev ua tshuaj lom neeg:Cov cuab yeej tuav cov tshuaj chlorides, acids, los yog tshuaj dawb huv.Khoom noj & dej haus:Cov cuab yeej siv cov tshuaj ntsev los yog kua qaub ntxuav.Pharmaceutical:Cov kab ke uas yuav tsum tau ua kom tsis muaj menyuam tsis tu ncua thiab tiv thaiv cov tshuaj ntxuav.Polluted Nroog/Industrial:Cov cheeb tsam uas muaj kua qaub los nag los yog kev lag luam poob. Siv 304L nyob rau hauv cov cheeb tsam no yuav luag yeej ua rau lub zos corrosion thiab tsis ua hauj lwm ntxov ntxov.

Cov molybdenum hauv 316L tshwj xeeb tiv thaiv chloride li cas -induced pitting?
Chloride ions tuaj yeem nkag mus thiab hauv zos ua txhaum cov txheej txheem tiv thaiv chromium oxide ntawm stainless hlau, pib lub qhov me me. Molybdenum integrates rau hauv cov txheej txheem passive no, ua rau nws tiv taus chloride ntau dua. Nws kuj tseem txhawb nqa qhov rov ua dua ntawm txhua qhov chaw me me puas, zoo "kho" qhov chaw ua ntej lub qhov dej tuaj yeem loj hlob. Cov txheej txheem no muab 316L ntau dua qhov pib rau chloride concentration thiab kub ua ntej pitting pib, ntsuas los ntawm nws qhov siab dua Pitting Resistance Equivalent Number (PREN).

Puas muaj tus nqi thiab kev tsim khoom lag luam- tawm thaum xaiv 316L?
Tau. 316L nqa tus nqi tseem ceeb tshaj 304L vim nws cov ntsiab lus molybdenum thiab npib tsib xee. Fabrication zoo ib yam, tab sis vuam 316L yuav tsum tau ceev faj muab cov hlau xaiv (xws li, 316L muab tub lim) los tiv thaiv corrosion hauv cov vuam. Nws lub zog me ntsis siab dua tuaj yeem xav tau ntau lub zog tsim. Txawm li cas los xij, rau daim ntawv thov tsim nyog, cov nqi no tsawg dua cov nqi ntawm kev hloov cov khoom siv corroded 304L, cuam tshuam nrog cov khoom sib kis, lossis ntsib teeb meem kev nyab xeeb.

Dab tsi yog qhov yooj yim, ua tsis tiav - txoj cai nyab xeeb rau cov kws tsim khoom thiab cov neeg yuav khoom ua raws?
Siv txoj cai no:Yog tias daim ntawv thov cuam tshuam nrog cov ntsev (seawater, de{0}}icing salts), chlorinated dej, tsis tu ncua noo noo nyob rau hauv industrial / ntug hiav txwv dej, los yog tshuaj ua, koj yuav tsum qhia 316L stainless hlau.Rau cov ntawv thov hauv tsev qhuav, cov qauv tsim vaj tsev nyob hauv cov huab cua qhuav hauv av, cov dej tsis huv, thiab cov khoom noj khoom haus dav dav uas tsis muaj chlorides, 304L yog qhov kev xaiv zoo tshaj plaws thiab pheej yig dua. Thaum tsis ntseeg txog ib puag ncig, xaiv 316L kom ntseeg tau tias lub neej ntev.